Practice Quiz on Crash Course: Digestive System, Part 2

This location is where mechanical and chemical digestion starts: (I) buccal cavity, (II) ingestion, (III) mouth, (IV) oral cavity.

• III only
• I and IV only
• III and IV only
• All except III
• All of these

The _____ forms the roof of the mouth and helps with food manipulation, while the _____ closes off the nasopharynx to direct food to the esophagus.

• teeth, tongue
• teeth, soft palate
• soft palate, hard palate
• hard palate, soft palate
• hard palate, tongue

What is the term for the mass of food formed in the mouth for swallowing?

• bolus
• chyme
• epiglottis
• saliva

Which of the following is NOT true about saliva?

• consists of 97 to 99.5 % water
• slightly acidic, w/ pH of 6.75 to 7
• contains amylase that breaks down lipids
• has antibodies and bacterial-fighting enzymes

Which of the following is NOT paired with it’s correct function?

• small intestine: absorption of nutrients
• mouth: propulsion of food to the stomach via peristalsis
• stomach: storage of food, mechanical and chemical digestion
• teeth and tongue: mechanical breakdown and manipulation of food

What special feature does the stomach’s muscularis layer have?

• An additional smooth muscle layer for extra strength
• Mucous cells that produce a protective coat against self-digestion
• The ability to secrete enzymes that accomplish chemical digestion
• A highly acidic environment that kills bacteria and viruses and denatures proteins

True or false: The stomach is able to store food, mechanically and chemically break down food, and absorb certain substances.

• True
• False

Which of the following cells is CORRECTLY paired with its secretion?

• chief cells: gastrin
• enteroendocrine cells: hormones
• G cells: HCl
• parietal cells: pepsinogen

What enzyme is activated by hydrochloric acid to help digest proteins in the stomach?

• amylase
• lipase
• pepsin
• trypsin

Identification: What substance is an inactive enzyme released by chief cells?